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Some factors prevent the no-tillage system (NTS) from being widely adopted in the Cerrado, among which stand out the high temperature and high rainfall characteristics of the biome that make it difficult to maintain the mulch on the ground and obtain the true NTS. The objective of this work was to recommend an arrangement between millet (Pennisetum glaucum) and crotalaria (Crotalaria spectabilis), when cultivated in intercropping for cover crops. The experiment was carried out in a typical Kandiustox (Oxisol), in a randomized block design with five treatments and four replications. The treatments consisted of: single crotalaria cultivation; single cultivation of millet; 25% crotalaria + 75% millet; 50% crotalaria + 50% millet; 75% crotalaria + 25% millet. Soil cover rate, root density, phytomass accumulation, nutrient content and accumulation, decomposition, half-life (T½), straw nutrient cycling and weed mass in each system were evaluated. C. spectabilis was suppressed by P. glaucum in the 25% crotalaria + 75% millet consortium. Although crotalaria has the highest N content, pearl millet has higher N accumulation in kg ha-1 due to higher dry matter production. Weed control was more efficient as the percentage of pearl millet increased as well as the number of roots. The 50% crotalaria + 50% millet intercropping is the most favourable arrangement between the two species, presenting intermediate values of cover rate, accumulation and decomposition of dry mass and nutrients, as well as weed control, keeping present in the system the characteristics of the two species. [ABSTRACT FROM AUTHOR]

The objective of this work was to select similarity measures and agglomeration methods most appropriate to cluster analysis to characterize the vertical and horizontal variability of resistance to penetration in Latossolo Vermelho Distrófico under degraded pasture. The PR was sampled at intervals of 10 mm until 300 mm depth, in 4 points spaced 0.50 m from the 30 vertices of a 6 x 10 m mesh and at 3 more sites with 18 radially distanced points by 0.125 m. AF and HCA were applied to evaluate the soil PR variability in depth and by HCA its horizontal dispersion too. The highest PR values was between 20 and 60 mm deep in 94.22% of the evaluated profiles and in the remaining 5.8%, thicker and deeper, this layer it was established between 60 and 190 mm. The HCA technique by algorithm of arithmetic mean linkage between group and, Euclidean distance coefficient proved efficient, as well as, AF in the evaluation of the vertical PR variability, resulting a stratification of the resistance profile more coherent with the dynamics of the PR in depth. The PR values in the soil under degraded pasture are higher than the critical limit, with the layer of 20 to 60 mm deep having the highest mechanical impedance. [ABSTRACT FROM AUTHOR]